CAS (Bosche Replacement) timer clock battery backup chlorinator pool time electronic FM1 BBU 
 
High quality timer with battery backup. Commonly used in Chlorinators including the below with battery back-up required: 
Crystal Clear
Waterlinx
Poolpro
Focus
Sapphire
& others.
 
Details:
240v 50Hz
Width - 60mm
Length - 60mm
Depth Overall - 33mm
Depth Face - 20mm
 
Will fit most generic cover in your chlorinator.
Cover not included with this listing but can be purchased separately either as a surround or as a surround & face cover.